Question

我正在尝试从YAML配置文件为活动记录记录器配置debuglevel，但是得到以下错误，除了在YAML中使用数字之外，我该怎么办呢？

sample.rb:30 warning: toplevel constant LEVEL referenced by Logger::LEVEL
"DEBUG"
ArgumentError: comparison of Fixnum with String failed

这里是sample.rb

require 'java'
require 'active_record'
require 'activerecord-jdbc-adapter'
require 'yaml'
require 'logger'

def get_jar_path
  if __FILE__[/.+\.jar!/] #in case run from JAR
    scriptpath = __FILE__[/(.*)\/.+\.jar!/]
    $1[6..-1]
  else #in case run with jRuby
    '..'
  end
end

def load_config
  path = "#{get_jar_path}/#{File.basename(__FILE__, ".*")}.configuration.yml"
  p path
  $conf = YAML::load_file(path)
end

load_config
LEVEL = $conf['debug_level'] #string 'DEBUG' from configuration file
$log = Logger.new( "#{get_jar_path}/log_#{Time.now.strftime("%Y%m%d")}.txt", 'monthly' )
ActiveRecord::Base.logger = $log
ActiveRecord::Base.logger.level = Logger::DEBUG #works
ActiveRecord::Base.logger.level = Logger::LEVEL #doesn't work
p ActiveRecord::Base.logger.level
$log.info "start #{__FILE__}"

Answer 1

可用的日志级别为:: debug，：info，：warn，：error，：fatal，和：未知，对应于从0到5的日志级别编号分别

http://guides.rubyonrails.org/debugging_rails_applications.html

require 'logger'

puts Logger::DEBUG

--output:--
0


str = "DEBUG"
puts Logger.const_get(str)

--output:--
0

所以你应该这样做：

level = $conf['debug_level'] #string 'DEBUG' from configuration file
$log = Logger.new( "#{get_jar_path}/log_#{Time.now.strftime("%Y%m%d")}.txt", 'monthly' )
ActiveRecord::Base.logger = $log
ActiveRecord::Base.logger.level = Logger.const_get(level)

我不确定为什么你认为在当前作用域中定义一个常量LEVEL会使该常量出现在Logger作用域中，这样你就可以编写Logger :: LEVEL。你基本上是这样做的：

MYCONST = "hello"

module SomeModule
  SOMECONST = "goodbye"
end

你可以写：

puts MYCONST   #=>hello

..你可以写：

puts SomeModule::SOMECONST  #goodbye

..但你不能写：

puts SomeModule::MYCONST

--output:--
1.rb:10:in `<main>': uninitialized constant SomeModule::MYCONST (NameError)

来自yaml文件的active_record配置：debuglevel

1 个答案: